Section 303(d) of the federal Clean Water Act (CWA) and the U.S. Environmental Protection Agencys (USEPA) implementing regulations direct each state to identify and list waters, known as water quality limited segments (WQLSs), in which current required controls of a specified substance are inadequate to achieve water quality standards. A water quality standard is the combination of a designated use for a particular body of water and the water quality criteria designed to protect that use. For each WQLS listed on the Integrated Report of Surface Water Quality in Maryland (Integrated Report), the State is to either establish a Total Maximum Daily Load (TMDL) of the specified substance that the waterbody can receive without violating water quality standards, or demonstrate via a Water Quality Analysis (WQA) that water quality standards are being met. The Rock Creek 8-digit watershed (basin number 02-14-02-06), located in Montgomery County, was identified on the Integrated Report under Category 5 as impaired by nutrients (1996 listing), suspended sediments (1996 listing), fecal bacteria (2002 listing) and evidence of impacts to biological communities (2002 listing). Two impoundments located within the basin, Needwood Lake and Lake Bernard Frank were identified as impaired by phosphorus in 1998. All impairments are listed for non-tidal streams. The 1996 nutrient listing was refined in the 2008 Integrated Report and phosphorus was identified as the specific impairing substance. Similarly, the 1996 suspended sediment listing was refined in the 2008 Integrated Report to a listing for total suspended solids. Water Quality Analyses for eutrophication in Needwood Lake and Lake Bernard Frank were approved by the USEPA in 2003. A TMDL to address the 2002 fecal coliform listing was approved by the USEPA in 2007.